Field of the Disclosure
The present subject matter relates to systems and methods for blood or blood component processing which include the addition of an anticoagulant to the blood or blood component during a blood processing procedure.
Background
Whole blood and/or blood constituents may be processed in a wide variety of ways with different objectives and goals. For example, in apheresis whole blood is routinely separated into its various components, such as red blood cells, platelets, mononuclear cells and plasma. This is popularly used for the purpose of collecting one or more specific blood components for later administration to patients in need of those blood components, but may also be used for therapeutic purposes, for example, to remove or reduce the amount of a particular blood component from a patient as part of a medical treatment.
In typical apheresis systems, whole blood is drawn from a donor and combined with an amount of anticoagulant to retard coagulation during further processing. The anticoagulated blood is then processed through the system to obtain the needed separation. The blood components that are not stored for later use or removed for therapeutic purposes are typically returned to the donor or patient. These procedures may be carried out alone or in combination with other procedures or systems, such as pathogen removal or inactivation processes and/or devices for removing or inactivating certain pathogens that may accompany a blood component being collected or returned to the donor or patient.
Typical blood processing systems employ separate anticoagulant and whole blood pumps, which operate at a fixed ratio of whole blood flow rate to anticoagulant flow rate. As a result, the operation of the pumps is effectively constrained or tied together according to the predetermined ratio, and the anticoagulant pump rate is dependent upon and varies with the whole blood pump rate. Hence, if the rate of the whole blood pump is changed during a blood processing procedure (e.g., varying the rate between a relatively high level to a relatively low level and back), the anticoagulant pump flow rate will also be changed proportionally to maintain the predetermined ratio.